Method and apparatus for forming combinatorial film

ABSTRACT

A combinatorial deposition method is characterized in that, in a method of performing thin-film coating onto a substrate disposed in a vacuum, two or more substrates are moved between a deposition position and a cooling position, sequentially only substrates to be coated is moved to the deposition position while substrates at the cooling position are cooled by a cooling mechanism, and substrates are respectively deposited under different deposition conditions in only one vacuum evacuation process. Various deposition conditions with regard to sputtering and the like are accurately controlled, so that coating films can be efficiently produced under different deposition conditions.

TECHNICAL FIELD

The present invention of the application relates to a combinatorialdeposition method and an apparatus thereof. More particularly, theinvention of the application relates to a combinatorial depositionmethod and an apparatus thereof in which various sputter depositionconditions can be accurately controlled, and coating films can beefficiently prepared under different deposition conditions.

BACKGROUND ART

Thin film coating onto a substrate is one effective material developmentmethod for enhancing the excellent function of a substrate material,adding a new function, or further increasing the life of the substratematerial and it is now drawing attention for its application inindustrial, biological, aerospace, and other varied fields. Forinvestigation of various thin layer compositions of such thin filmcoatings, a deposition apparatus using a combinatorial method, and amasking mechanism that can prepare a thin film in correspondence with a3-dimensional diagram have been proposed (e.g. patent document 1), andthus thin film composition that can generate new properties can beefficiently found.

On the other hand, for the investigation of thin film conditions,experiments and evaluations of many kinds of deposition conditions,where a large number of deposition condition parameters are changedlittle by little, are needed, and the best conditions have not been ableto be determined without tremendous labor, time and other difficulties.For example, in thin film coating prepared by sputtering, properties ofobtained coating films are largely influenced by many depositioncondition parameters such as sputter gas pressure, gas type, partialpressure, sputter power value, substrate temperature, distance betweenthe substrate and a target, and sample bias, in addition to thecomposition and combination of sputter materials. Therefore, althoughexperiments where each of the deposition condition parameters is changedare needed for determining the best conditions, actually, in most cases,evaluation has been conducted on experiments where only one or two kindsof deposition condition parameters are changed, and it has been almostimpossible that the deposition conditions have been optimized withregard to all the various properties of the obtained coating films.

Patent document 1: JP-A-2004-035983.

However, if the thin film coating were performed under many depositionconditions whose parameters are accurately controlled, andcharacteristics of the coating films are evaluated, the best depositionconditions that optimize each of the properties of the coating filmscould be determined. Therefore, a deposition method and an apparatus inwhich the parameters can be controlled accurately and efficiently aredesired.

Thus, the subject of the invention of the application, which was made inthe light of the above circumstances, is to provide a method and anapparatus thereof, in which the problems in the conventional art aresolved, many deposition condition parameters of sputter coating and thelike can be accurately controlled, and many kinds of coating films underdifferent deposition conditions are produced efficiently with theparameters being changed little by little. Such combinatorial depositionis realized, thereby the optimum conditions of each of the properties(frictional property, electrical conductivity, optical property, thermalproperty and the like) of the coating films can be easily determined,which is extremely useful for developing a new material.

DISCLOSURE OF THE INVENTION

To solve the above problems, first, the invention of the applicationprovides a combinatorial deposition method characterized in that, in amethod for performing the thin-film coating onto a substrate disposed invacuum, two or more substrates can be moved to a deposition position ora cooling position, and in one vacuum evacuation process, whilesubstrates are held at the cooling position where the substrates arecooled by a cooling mechanism, only objective substrates to be coatedare sequentially moved to the deposition position and subjected todeposition.

Second, the invention of the application provides a combinatorialdeposition method characterized in that the deposition is performed totwo or more substrates with the deposition conditions different for eachsubstrate; third, it provides a combinatorial deposition methodcharacterized in that the two or more substrates can be moved to thedeposition position or the cooling position by a rotation mechanism;fourth, it provides a combinatorial deposition method characterized inthat a water- or liquid nitrogen-cooling mechanism is adopted; fifth, itprovides a combinatorial deposition method characterized in that thedeposition is performed by sputtering with any one or more of thefollowing deposition conditions: sputter gas pressure, sputter gas,partial pressure, sputter power value, substrate temperature, distancebetween a substrate and a target, and sample bias, and the conditionsare different for each substrate in one vacuum evacuation process.

Furthermore, sixth, the invention of the application provides acombinatorial deposition apparatus characterized in that the apparatusperforms thin-film coating onto the substrate disposed in a vacuum,wherein a sample holder can hold two or more substrates, and eachsubstrate can be moved to a deposition position or a cooling position,and in one vacuum evacuation process, while substrates at the coolingposition are cooled by the cooling mechanism, only objective substratesto be coated are sequentially moved to the deposition position andsubjected to deposition.

Moreover, seventh, the invention of the application provides acombinatorial deposition apparatus characterized in that the depositionis performed on the two or more substrates with the depositionconditions different for each substrate; eighth, it provides acombinatorial deposition apparatus characterized in that the two or moresubstrates can be moved to the deposition position or the coolingposition by a rotation mechanism; ninth, it provides a combinatorialdeposition apparatus characterized in that even if the substrate at thedeposition position is heated to 1000° C. or more, the rise intemperature in the substrates at the cooling position can be restrainedwithin 100 K; tenth, it provides combinatorial deposition apparatuscharacterized in that a water- or liquid nitrogen-cooling mechanism isadopted as a cooling mechanism; eleventh, it provides combinatorialdeposition apparatus characterized in that the apparatus is fordeposition by sputtering, wherein in one vacuum evacuation process,deposition can be performed for two or more substrates by varying anyone or more of the following deposition conditions: sputter gaspressure, sputter gas type, partial pressure, sputter power value,substrate temperature, distance between a substrate and a target, andsample bias; twelfth, it provides combinatorial deposition apparatuscharacterized in that a valve for controlling sputter gas pressure isprovided and a feedback mechanism changing conductance so as to controlthe sputter gas pressure at a prescribed value is provided; thirteenth,it provides combinatorial deposition apparatus characterized in that thedistance between the substrate and the target can be controlled by astraight-line introducing mechanism; fourteenth, it provides acombinatorial deposition apparatus characterized in that a turbomolecular pump is provided as a vacuum evacuation mechanism; fifteenth,it provides a combinatorial deposition apparatus characterized in that asubstrate for Suzuki-type friction test can be mounted; and sixteenth,it provides a combinatorial deposition apparatus characterized in that aposition of the sample holder or a sputter source is variable, anddeposition can be performed for a substrate cooled by the coolingmechanism.

In addition, seventeenth, the invention of the application provides asample holder characterized in that the sample holder has a rotationmechanism that can hold two or more samples, wherein while a sample notto be subjected to deposition is cooled at the cooling position by thecooling mechanism, only a sample to be subjected to deposition issubjected to temperature control at the deposition position; eighteenth,it provides a sample holder characterized in that even if the substrateat the deposition position is heated to 1000° C. or more, the rise intemperature of the substrates at the cooling position can be restrainedwithin 100° K; and nineteenth, it provides a sample holder characterizedin that a water- or liquid nitrogen-cooling mechanism is adopted as thecooling mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view schematically illustrating a general configuration of acombinatorial coating apparatus of the invention of the application;

FIG. 2 is a graph illustrating change in friction coefficient of a thinfilm deposited with different substrate temperature using acombinatorial coating apparatus of the invention of the application; and

FIG. 3 is a graph illustrating change in friction coefficient of a thinfilm deposited with different oxygen partial pressure using acombinatorial coating apparatus of the invention of the application.

References in the figures indicate as follows:

-   -   1 chamber,    -   2 sample holder,    -   3 sputter source,    -   4 evacuation system,    -   5 inert-gas supply port,    -   6 reactive-gas supply port,    -   7 heater,    -   8 cooling mechanism,    -   9 valve,    -   11 view port, and    -   21 substrate.

BEST MODE FOR CARRYING OUT THE INVENTION

The invention of the application has the features as the above, andhereinafter, embodiments of it are described. The most distinctivefeature is that, in the invention of the application, deposition can beperformed under various deposition conditions in one vacuum evacuationprocess. For example, deposition according to a combinatorial manner inwhich many deposition conditions are changed little by little can berealized accurately and simply.

A combinatorial deposition method of the invention of the application ischaracterized in that in a method of thin film coating to on a substratedisposed in a vacuum, it is possible for two or more substrates to bemoved to the deposition position or the cooling position, and in onevacuum evacuation process, only objective substrates to be coated aresequentially moved to the deposition position and subjected todeposition, while the substrates at the cooling position are cooled bythe cooling mechanism.

As the method of thin film coating onto the substrate disposed in avacuum, to which the combinatorial deposition method of the presentinvention is applied, various known deposition methods includingphysical vapor deposition (PVD) such as sputter or vacuum evaporation,and chemical vapor deposition (CVD) such as thermal decompositionreaction, reactive evaporation and chemical transport, can be used. Morespecifically, for example, magnetron sputter, molecular beam epitaxy, orpulse laser evaporation can be considered.

In the combinatorial deposition method of the application, to performthe deposition for two or more substrates, each substrate can be movedto a deposition position or a cooling position. Then, in one vacuumevacuation process, only objective substrates to be coated aresequentially moved to the deposition position and subjected to thedeposition while the substrates at the cooling position are cooled bythe cooling mechanism. The number of substrates is not particularlylimited, and can be appropriately determined in consideration ofsubstrate size, size of apparatus for deposition, the number ofdeposition conditions and the like. As moving means of the two or moresubstrates, which is not particularly limited, various mechanisms andstructures can be considered. For example, a moving means using arotation mechanism such as turntable, a belt conveyer, and further amoving means having an up-and-down function can be exemplified. Inaddition, a cooling mechanism is not particularly limited, and forexample, cooling using a refrigerant such as liquid nitrogen, liquidhelium, or water can be exemplified. In particular, in the invention ofthe application, a water cooling mechanism with water circulation orliquid-nitrogen cooling mechanism is simple and preferable.

For the substrate at the deposition position, substrate temperature canbe controlled according to deposition conditions. Specifically, forexample, the substrate can be subjected to deposition while beingheated, or the substrate can be subjected to deposition without heating,or the substrate can be also subjected to deposition while being cooled.

In this way, deposition is sequentially performed for only objectivesubstrates to be coated, while other substrates are cooled, so thatdeposition can be performed for two or more substrates in one vacuumevacuation process. In deposition, deposition conditions can be changedfor each substrate. Thus, in one vacuum evacuation process, depositionaccording to a combinatorial manner in which many deposition conditionsare changed little by little can be realized.

More specifically, for example, regarding deposition by sputtering, inthe combinatorial deposition method of the invention of the application,deposition can be performed for many substrates with varying any one ormore of the following deposition conditions in one vacuum evacuationprocess: sputter gas pressure, sputter gas type, partial pressure,sputter power value, substrate temperature, distance between a substrateand a target.

The combinatorial deposition method as above can be simply realized by acombinatorial deposition apparatus provided by the invention of theapplication. Thus, the combinatorial deposition apparatus of theinvention of the application is characterized in that the apparatus isfor performing thin film coating for the substrates disposed in vacuum,wherein a sample holder can hold two or more substrates and move eachsubstrate to a deposition position or a cooling position, and onlyobjective substrates to be coated are sequentially moved to thedeposition position and subjected to the deposition while the substratesat the cooling position are cooled by the cooling mechanism, in onevacuum evacuation process.

The combinatorial deposition apparatus of the invention of theapplication have various configurations according to various thin-filmcoating methods, but the sample holder is distinctive. In the sampleholder, two or more substrates can be held and each substrate can bemoved to a deposition position or a cooling position. The number ofsubstrates that can be held is not particularly limited, and can beappropriately determined in consideration of the size of a substrate,size of an apparatus for deposition, the number of deposition conditionsand the like. The sample holder is exchangeable according to conditionssuch as a substrate. A moving means of two or more substrates is notparticularly limited, and various mechanisms and structures can beconsidered. For example, a moving means using a rotation mechanism suchas a turntable, a belt conveyer, or a moving means having an up-and-downfunction can be exemplified. In the invention of the application, it issimple and preferable that two or more substrates can be moved to adeposition position or a cooling position by a rotation mechanism.Moreover, a cooling mechanism is not particularly limited, and forexample, cooling using a refrigerant such as liquid nitrogen, liquidhelium, or water can be exemplified. In the invention of theapplication, a water cooling mechanism with water circulation or aliquid nitrogen cooling mechanism is illustrated as a simple andpreferable example.

Thus, for example, a sample holder provided by the invention of theapplication is characterized in that the sample holder has a rotationmechanism that can hold two or more samples, wherein it is possible forsamples not to be coated to be cooled by a cooling mechanism at acooling position, and for only samples to be coated to be subjected totemperature control at a deposition position. More specifically, forexample, as illustrated in FIG. 1, a sample holder (2) has a turntable,and substrates (21) are disposed on the turntable in an approximatelycircular pattern. Near a deposition position, a heater (7) for heatingis arranged and near cooling positions, a cooling mechanism (8) with acooling pipe is arranged, so that temperature of the substrate (21) atthe deposition position can be controlled to a desired depositiontemperature and then subjected to the deposition while substrates (21)at the cooling position are cooled. According to the configuration, forexample, even if the substrate (21) at the deposition position is heatedto 1000° C. or more, the rise in temperature of the substrates (21) atthe cooling position can be restrained within 100 K. Moreover, since thesubstrate (21) can be moved between the deposition position and thecooling position by rotating the turntable, only the substrate (21) thatis moved to the deposition position is sequentially subject todeposition. Thus, deposition can be performed by varying depositionconditions for each substrate (21). Therefore, the sample holder (2) ofthe invention of the application makes it possible to perform depositionaccording to a combinatorial manner in various thin-film coating method.

For example, a combinatorial deposition apparatus provided by theinvention of the application may be for deposition by sputtering,wherein deposition can be performed for two or more substrates byvarying any one or more of the following deposition conditions: sputtergas pressure, sputter gas, partial pressure, sputter power value,substrate temperature, distance between a substrate and a target, andsample bias, in one vacuum evacuation process. The sputtering depositionapparatus may be, for example, illustrated in FIG. 1, in which a sampleholder (2) and a sputter source (3) are installed in a chamber (1), anda vacuum evacuation mechanism (4) and supply ports (5), (6) for inertgas and reactive gas are provided. In such a combinatorial depositionapparatus, a valve (9) for controlling sputter gas pressure may have afeedback function for changing conductance so that the pressure becomesa prescribed value. Sputter gas pressure can be set accurately andreproducibly. The distance between the substrate (21) and a target canbe controlled by the straight-line introducing mechanism for the sputtersource (3). Furthermore, a turbo molecular pump and the like areprovided as the vacuum evacuation mechanism (4), so that, for example,in a vacuum system of the apparatus, ultra high vacuum of about 10⁻⁵ Pacan be realized in a shorter time. The sample holder (2) is configuredso that a substrate (21) suited for the Suzuki friction test can bemounted, and thus various property evaluation of coating thin-filmsproduced can be performed more simply.

The combinatorial deposition apparatus of the invention of theapplication is further characterized in that a position of the sampleholder (2) or the sputter source (3) is variable and deposition can beperformed for a substrate (21) cooled by the cooling mechanism (8).Thus, for example, by arranging a deposition position near the coolingmechanism (8) and by changing a position of the sample holder (2) or thesputter source (3), deposition can be performed for a substrate (21)while being cooled.

According to the invention of the application, by changing variousdeposition conditions are changed little by little, many coatingthin-films different in natures such as crystallinity and crystalorientation can be manufactured efficiently. And by evaluating variousproperties such as frictional properties, electrical conductivity,optical properties, and thermal properties of the various obtainedcoatings, many deposition condition parameters can be optimized moresimply and surely and possibility of development of a new functionalcoating film is remarkably expanded.

Hereinafter, an embodiment of the invention of the application isfurther described in detail. It goes without saying that the inventionis not limited to the following example and various modifications arepossible.

EXAMPLE

FIG. 1 is a view schematically illustrating a general configuration ofan example of a combinatorial coating apparatus of the invention of theapplication. The combinatorial coating apparatus is a depositionapparatus using magnetron sputter and is composed of a main chamber (1),a multi-sample holder (2) and a sputter source (3) built in the mainchamber (1), a vacuum evacuation system (4) connected to the mainchamber (1), an inert-gas supply port (5), a reactive-gas supply port(6) and the like. A view port (11) of ICF305 size is provided at a frontof the main chamber (1), and thus the multi-sample holder (2) can beefficiently taken in and out. Regarding the sputter gun (3), a positioncan be changed using a straight-line introducing mechanism (not shown),so that the distance between the substrate (21) to be deposited and thetarget can be controlled. The vacuum evacuation system (4) has a turbomolecular pump having throughput of 600 l/s, which can perform vacuumevacuation of 10⁻⁵ Pa in a short time. Regarding a valve (9) forcommunicating between the main chamber (1) and the vacuum evacuationsystem (4), opening and closing can be controlled by feedback thatconductance is varied so that a prescribed pressure is attained, andthereby accurate setting of the sputter gas pressure can be achievedrepeatedly.

A plural number of substrates (21), 14 in the case of FIG. 1, can bemounted on the multi-sample holder (2) and can be sequentially moved byrotation using the rotation mechanism. A substrate (21) to be depositedis moved to a deposition position near a heater (7) and the other 13substrates (21) are disposed at a cooling position near a water coolingmechanism (8). Even if the substrate (21) to be deposited is heated toapproximately 1000° C. by the heater (7), the other 13 samples arecooled by the cooling mechanism (8), so that the rise in temperature ofthese samples can be restrained within 100 K and only the objectivesubstrate (21) can be deposited. According to such a configuration,deposition conditions can be accurately varied for each substrate (21)and, for example, 14 kinds of deposition conditions are realized in onevacuum evacuation process. Since the multi-sample holder (2) can bemounted with a substrate suited for the Suzuki friction test, propertytests of coating films deposited can be efficiently conducted.

The change in friction coefficients of the films produced under variousdeposition conditions using the combinatorial coating apparatusdescribed above was examined. FIG. 2 illustrates change in frictioncoefficient in the case where deposition was performed under 8 differentsubstrate temperatures. FIG. 3 illustrates change in frictioncoefficient in the case where deposition was performed under 8 differentoxygen partial pressures. Furthermore, change in friction coefficientcould be examined in the case that deposition was performed underdifferent substrate temperatures and different partial pressures. Inthis way, respective thin films deposited under different depositionconditions can be obtained in one vacuum evacuation process, andevaluation of various properties of the obtained coating films andoptimization of the deposition conditions of the films can be easilyperformed.

INDUSTRIAL APPLICABILITY

According to the invention of the application, a combinatorialdeposition method and an apparatus thereof are provided, in whichvarious conditions for deposition by sputtering and the like can beaccurately controlled, and coating films can be efficiently producedunder different deposition conditions.

1. A combinatorial deposition method characterized in that, in a methodof performing thin-film coating on a substrate disposed in a vacuum, twoor more substrates can be moved to a deposition position or a coolingposition, and sequentially only substrates to be coated are moved to thedeposition position and subjected to deposition while substrates at thecooling position are cooled by a cooling mechanism, in one vacuumevacuation process.
 2. The combinatorial deposition method according toclaim 1, characterized in that deposition is performed for the two ormore substrates with different deposition conditions for each substrate.3. The combinatorial deposition method according to claim 1,characterized in that the two or more substrates can be moved to thedeposition position or the cooling position by a rotation mechanism. 4.The combinatorial deposition method according to claim 1 characterizedin that a water- or liquid nitrogen-cooling mechanism is used.
 5. Thecombinatorial deposition method according to claim 1 characterized inthat deposition is performed by sputter with any one or more of thefollowing deposition conditions: sputter gas pressure, sputter gas type,partial pressure, sputter power value, substrate temperature, distancebetween the substrate and a target, and sample bias, which are variedfor each substrate in one vacuum evacuation process.
 6. A combinatorialdeposition apparatus characterized in that the apparatus performsthin-film coating onto a substrate disposed in a vacuum, wherein asample holder can hold two or more substrates, and each substrate can bemoved to a deposition position or a cooling position, and sequentiallyonly substrates to be coated are moved to the deposition position andsubjected to deposition while substrates at the cooling position arecooled by a cooling mechanism, in one vacuum evacuation process.
 7. Thecombinatorial deposition apparatus according to claim 6, characterizedin that deposition is performed for the two or more substrates withdifferent deposition conditions for each substrate.
 8. The combinatorialdeposition apparatus according to claim 6 characterized in that the twoor more substrates can be moved to the deposition position or thecooling position by a rotation mechanism.
 9. The combinatorialdeposition apparatus according to claim 6 characterized in that even ifa substrate at the deposition position is heated to 1000° C. or more,rise in temperature of substrates at the cooling position can berestrained within 100 K.
 10. The combinatorial deposition apparatusaccording to claim 6 characterized in that a water- or liquidnitrogen-cooling mechanism is used.
 11. The combinatorial depositionapparatus according to claim 6, characterized in that the apparatus isfor deposition by sputtering, and deposition can be performed for two ormore substrates with any one or more of the following depositionconditions: sputter gas pressure, sputter gas, partial pressure, sputterpower value, substrate temperature, distance between the substrate andtarget, and sample bias, which are varied for each substrate, in onevacuum evacuation process.
 12. The combinatorial deposition apparatusaccording to claim 11, characterized in that a valve for controlling thesputter gas pressure has a feedback function of changing conductance sothat the pressure is equal to a prescribed value.
 13. The combinatorialdeposition apparatus according to claim 11, characterized in that thedistance between the substrate and the target can be controlled by astraight-line introducing mechanism.
 14. The combinatorial depositionapparatus according to claim 6, characterized in that a turbo molecularpump is provided as a vacuum evacuation mechanism.
 15. The combinatorialdeposition apparatus according to claim 6, characterized in that asubstrate suited for the Suzuki friction test can be mounted.
 16. Thecombinatorial deposition apparatus according to claim 6, characterizedin that a position of the sample holder or a sputter source is variable,wherein deposition can be performed for a substrate cooled by thecooling mechanism.
 17. A sample holder characterized in that the sampleholder has a rotation mechanism that can hold two or more samples,wherein it is possible for samples not to be coated to be cooled by acooling mechanism at a cooling position, and for only samples to becoated to be subjected to temperature control at a deposition position.18. The sample holder according to claim 17, characterized in that evenif a substrate at the deposition position is heated to 1000° C. or more,rise in temperature of substrates at the cooling position can berestrained within 100 K.
 19. The sample holder according to claim 17,characterized in that a water- or liquid nitrogen-cooling mechanism isused.